When police found a Davenport man dead in his apartment in June, several factors led them to think he died of natural causes.

Then came an anonymous tip.

Police now say Kevin O'Connell, 48, was strangled. It is likely his apartment at 1425 E. 39th St. was the crime scene.

A man who already was in the Scott County Jail on an unrelated charge was arrested Friday on suspicion of first-degree murder. Police are accusing Stephen A. Boeding of strangling O'Connell on May 25, which was 12 days before the body was found.

A tipster told police O'Connell and Boeding, 37, were drinking together at the time of the strangulation.

Davenport police investigators traveled about two weeks ago to Springfield, Ill., where O'Connell had been buried. His family consented to having his body exhumed, and an autopsy confirmed strangulation was the cause of death, police said.

Contacted Monday, O'Connell's mother said, "At this time, we don't have anything to say."

Davenport Police Major Don Schaeffer said part of the reason investigators did not initially detect signs of strangulation was the body's advanced state of decomposition. But also, O'Connell had health problems and had been under a doctor's care twice during the 30-day period leading up to his death. In Iowa, an autopsy is mandatory if a person has died without the need for medical attention in the 30 days prior to death, Schaeffer said.

Adding to the appearance of a natural death, when responding to a call to check O'Connell's welfare, police found his apartment door secured, and officers had to force it open. He was found in his bed. Police now believe the scene was staged.

Though it did not appear suspicious, the police department's crime-scene technicians processed the scene, Schaeffer said.

The photos taken that day paid off in the end, he said.

"It's a perfect example of why we do it — in case we have to go back to the scene," he said.

After getting the anonymous tip, Detective Bill Thomas took what he had on the case to Schaeffer, he said.

"I definitely thought it was worth looking into," he said. "He ran with it after he got the tip. I think you have to take your hat off to Detective Thomas. He did a great job, re-interviewed countless people. He did an extraordinary job on it — above and beyond, going with those hunches and being able to validate them."

Iowa court records show Boeding had a record of alcohol-related legal troubles, including three convictions for OWI. He also was regarded as a habitual traffic offender and has been arrested several times for assault. He was being held Monday without bond.